CHRISTCHURCH — New Zealand's earthquake death toll was confirmed at 71 with more bodies still be recovered but it was not known how many people might still be trapped in wrecked buildings in Christchurch, a government minister said on Thursday.

Rescue teams combed through rubble under searchlights for any survivors from Tuesday's 6.3-magnitude earthquake, which levelled large parts of the country's second-biggest city, but no more survivors were found.

"We have currently in morgues across the city 71 people confirmed dead, we are aware there are other bodies but we haven't got a number on that," Civil Defence Minister John Carter told reporters.

He said early reports of up to 300 people missing was speculation.

No further survivors were found overnight.

A national state of emergency has been declared and the central city has been under curfew with soldiers patrolling in armoured personnel carriers.

Thousands of people spent a second night in emergency shelters set up in local schools, sports grounds, and at a race course. Fresh water supplies were being distributed from schools and portable toilets set up around the city as services were disrupted.

The city has been shaken by more than 100 aftershocks since the initial magnitude 6.3 shake, bringing down more debris.